JAK2

This gene encodes a non-receptor tyrosine kinase that plays a central role in cytokine and growth factor signalling. The primary isoform of this protein has an N-terminal FERM domain that is required for erythropoietin receptor association, an SH2 domain that binds STAT transcription factors, a pseudokinase domain and a C-terminal tyrosine kinase domain. Cytokine binding induces autophosphorylation and activation of this kinase. This kinase then recruits and phosphorylates signal transducer and activator of transcription (STAT) proteins. Growth factors like TGF-beta 1 also induce phosphorylation and activation of this kinase and translocation of downstream STAT proteins to the nucleus where they influence gene transcription. Mutations in this gene are associated with numerous inflammatory diseases and malignancies. This gene is a downstream target of the pleiotropic cytokine IL6 that is produced by B cells, T cells, dendritic cells and macrophages to produce an immune response or inflammation. Disregulation of the IL6/JAK2/STAT3 signalling pathways produces increased cellular proliferation and myeloproliferative neoplasms of hematopoietic stem cells. A nonsynonymous mutation in the pseudokinase domain of this gene disrupts the domains inhibitory effect and results in constitutive tyrosine phosphorylation activity and hypersensitivity to cytokine signalling. This gene and the IL6/JAK2/STAT3 signalling pathway is a therapeutic target for the treatment of excessive inflammatory responses to viral infections. Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, Jul 2020]

Description

Janus kinase 2

Tissue specificity

Low tissue specificity

Subcell location

Nucleoplasm, Plasma membrane, Focal adhesion sites

Predicted location

Intracellular

Protein family

Cancer-related genes
Disease related genes
Enzymes
FDA approved drug targets
Human disease related genes
Mapped to neXtProt
Mapped to UniProt SWISS-PROT
Metabolic proteins
Plasma proteins
Predicted intracellular proteins
Protein evidence (Ezkurdia et al 2014)
Protein evidence (Kim et al 2014)

Chromosome

9 (4984390 - 5129948)

Ensembl ID

ENSG00000096968  (ver. 103.38)

Orthologs

Mouse Jak2: ENSMUSG00000024789

UniProt

O60674

neXtProt

NX_O60674

Human splice variants
Mouse splice variants

Protein structure